The development of larger and more powerful farm tractors has allowed agricultural implements such as cultivators and the like, to also increase in size. As will be appreciated, the larger size agricultural implements permit working of increasingly larger swatches of a field during each pass thereover. Thus, multi-sectional agricultural implements have been developed including a wheeled center or main section and one or more wheeled lateral wing sections connected on opposite lateral sides of the main section.
The central or main section of the implement is of an appropriate narrow width to pass through gate openings or along roads and highways. When the wing section is arranged laterally adjacent to the main section, however, it is often difficult to move such an implement through fence gates or along roads or highways. To reduce its extended lateral sides, most farm implements are provided with a hinge connection between the main and wing sections.
In addition to ground working tools carried thereon, many agricultural implements are provided with relatively large material receiving hoppers. These hoppers are provided on both the main section and the wing section of the agricultural implement. Such hoppers contain particulate or liquid materials such as fertilizers and the like and are of considerable weight when full. Moreover, the configuration of the hoppers is such that they cannot be moved to an inverted position without loss of materials contained therewithin. Thus, a hinge connection which allows a wing section to be elevated to an overhead folded transport position is not suitable for use on all types of agricultural implements.
Agricultural implements having one or more rearwardly folding wing sections are also known in the art. In this form of implement, the wing section extends laterally with respect to the center section during operation, and folds rearwardly with respect to the path travelled by the tractor to provide a transporting configuration whereby the width of the implement becomes narrow enough for passage through gates and fences and for negotiation of roadways over which it is pulled by the tractor.
A problem sometimes exists with implements having rearwardly folding wing sections. Each wing section of such an implement is pivotally connected to the main or center section through a pivot mechanism including a pivot pin defining a generally vertical axis about which the wing section moves. While allowing for horizontal pivoting movement, the pivot mechanism restricts or inhibits vertical movement of the wing section relative to the center section. The rigid pivot connection between the wing and center sections fails to allow independent vertical movement of the wing section relative to the center section. Thus, when the implement is operated on hillsides or other slanted or otherwise uneven ground contours, the elevation of the wing section can adversely affect the performance of the ground engaging tools on the center section and vice versa. Of course, when the ground engaging tools on either section are removed from ground contact, the efficiency added to the implement by the laterally extended wing section is lost or substantially reduced.
Thus, there is a need and a desire for an agricultural implement having a wing section which is pivotally connected for folding movement in essentially the same horizontal plane as the center section between a folded position and a working position and wherein the pivotal connection furthermore allows independent vertical movement of the wing section relative to the center section when in a working position thereby allowing for changing ground contours.